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Piscataway Wastewater Treatment Plant

Regional Wastewater Plant

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This sophisticated treatment plant was built in the environmentally sensitive area of Piscataway Creek as it flows into the Potomac. The plant is owned and operated by the Washington Suburban Sanitary Commission (WSSC). Initial construction was completed in 1967 and the plant's primary and secondary treatment capacity was expanded to 30 million gallons per day in 1974. In 1981, the advanced treatment portion of the plant went into service providing superb removal of suspended solids, organics, ammonia, nitrogen, and phosphorus. Phosphorus is considered one of the key ingredients in fostering the growth of nuisance algae in the river. In the 1960s, huge mats of algae formed along the banks of the lower Potomac, prompting strict requirements for wastewater treatment at all plants that discharge into the lower river. By removing phosphorus, the plant helps protect the delicate balance of the Potomac estuary. The Piscataway plant's in-house laboratory monitors the plant process, and computers automatically control most of the plant equipment. The plant discharges directly into the mainstream of the Potomac River via a 3 1/2-mile pipeline.

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Contact Information
Washington Suburban Sanitary Commission
11 Farmington Road West
Accokeek MD 20607

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